Dry wall grinding machine



FIG. 1 is a front elevational view of a dry wall grinding machine showing our new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a bottom view thereof;

FIG. 5 is a left side view thereof; and,

FIG. 6 is a right side view thereof. 

The ornamental design for a dry wall grinding machine, as shown. 